The invention relates to an x-ray diagnostic system for angiographic radiographs, comprising a patient support, an x-ray tube, arranged on one side of the support, supplied by an x-ray high voltage generator, an x-ray image intensifier, arranged on the other side of the support, with an associated television chain, a control loop for controlling the mean image brightness, and a syringe for contrast medium injection.
An x-ray diagnostic system of this type is described in the journal "Electromedica", 1/1977, on pages 2 through 6. Regarding this known x-ray diagnostic system, for the purpose of avoiding false estimations of the contrast medium flow velocity, and hence for the purpose of avoiding a faulty program selection, the proposal is made that the contrast medium velocity be measured and, on the basis of the measured value, the respectively optimum program be selected. The measurement of the contrast medium velocity proceeds in such a manner that the time is detected which the contrast medium requires to travel from the injection location to a specific measuring location, for example lying in the knee region, and that from such time measurement, and from the distance between the injection location and measuring location, the contrast medium velocity is calculated.